Online shopping records were broken during Cyber Monday, but mobile and website performance monitoring firm Keynote reveals that mobile retail sites were taking twice as long to load than normal.

Mobile retail sites usually take around 8-9 seconds to load. However, during one of the heaviest shopping days in history, Cyber Monday, they were taking, on average, 18 seconds to load, according to Keynote's Mobile Commerce Index. That's approximately seven times slower than the same websites' traditional pages on Cyber Monday.

With the number of people shopping from a smartphone or tablet, this rise in load time for mobile websites can have a significant impact on revenues.

"This is quite detrimental and will certainly impact a customer's experience negatively, and can easily motivate a shopper to abandon a site altogether or go to a competitor's mobile shopping site," said Aaron Rudger, mobile and web performance manager at Keynote.

Rudger attributes the problems with load times to a lack of testing before the holiday season traffic kicked in.

"Retailers put significant revenue at risk by not doing the requisite amount of mobile testing and mobile load testing to succeed and deliver an optimal experience during the holidays," he said. "The amount of holiday shopping now taking place on smartphones has simply grown too large for retailers to ignore. Simply put, retailers ignore the mobile experience at their own peril."

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